28 DECIDUOUS ERTJIT INSECTS AND INSECTICIDES. 



1868, infesting seeds of several varieties of cultivated grapes, namely, 

 Clinton, Delaware, Rogers No. 4, and an unnamed seedling variety. 

 Since that time, however, this insect has failed to materialize as a 

 serious enemy to cultivated varieties of grapes. The adult is a minute 

 hymenopterous fly. The female insect deposits its eggs by means of 

 its long ovipositor through the pulp of the grape berry into the seed. 

 The larva hatching from this egg is a minute grub, which feeds upon 

 the pulp within the seed, in which it reaches full development. 

 Grape berries infested by this pest shrivel and drop before the ripen- 

 ing period. This shriveled condition of the berries infested by this 

 grape-seed chalcis is the only evidence of its injury that is likely to 

 be confused with that of the larva of the grape-berry moth. 



DESCRIPTION. 

 THE EGG. 



The eggs of the grape-berry moth are oval, scale-like, semitrans- 

 parent bodies about 1.75 mm. by 1.25 mm. in diameter. They are 

 solidly glued to the surface of the berry and although quite flat they 

 are somewhat more rounded and smaller than those of the codling 

 moth, which they greatly resemble. Before the larvae hatch from 

 them the eggs are not very conspicuous, especially upon the green 

 berries, since on account of their transparency they become lost in 

 the ground color of the berry. The eggshell is finely reticulate. 

 The development of the larva can be readily observed through the 

 transparent shell. After the larva hatches the eggshell remains upon 

 the surface of the berry and can be more readily seen than the egg 

 itself and appears as a whitish spot possessing a pearly iridescence. 

 Upon the purple background of the ripening fruit the eggs are much 

 more conspicuous than upon the green berries, as shown in figure 7. 

 The eggs witli dark centers have been parasitized by the egg parasite 

 Trichogramma pretiosa Riley. 



THE LARVA. 1 



Larva: — 9 to 10 mm. Cylindrical, rather robust, tapering from [segment] 4 to head 

 and [segment] 8 to anal segment. Pale olivaceous-green, with a reddish or purplish 

 tinge from food. Head flattened, slightly bilobed, luteous green on upper parts of 

 lobes, discolored by brown in front; mouth parts and a horizontal dash on side of 

 each lobe below middle black. Pro-thoracic shield large but narrow, luteous brown, 

 bisected by pale green dorsal line. Thoracic feet black, green between joints. Tuber- 

 cles plates moderate, a slight shade darker than skin, shining. Anal plate not chitin- 



i Description by W. D. Kearfott, Trans. Amer. Ent. Soc., vol. 30, p. 293, 1904. 



